Your need for a still digital camera will be primarily to shoot blind, using the built-in flash, during investigations.  You'll be trying to capture images not readily apparent to the naked eye.  This means you need not spend an enormous amount on this particular tool . . . all you need is a decent file size (2 megs will suffice), a reliable flash, and a fixed focus lens that requires no fussing around with focus buttons or wheels.

Modes: Still Photos/Digital Video/PC Camera/Removal hard disk

Image sensor: 2.0 Megapixel CMOS sensor /4.0MP pictures via interpolation

Internal Memory: 16MB

External: MMC or SD card

Resolution: 4.0M Pixels: 2304x1728 Pixels Interpolation, 3.0M Pixels: 2048x1536pixels, 2.0M Pixels: 1600x1200pixels, 1.3M Pixels: 1280x1024pixels, 300K Pixels: 640x480pixels

PC Camera Mode: VGA:640x 480pixels, QVGA:320x240pixels

File Formats: JPEG

LCD Viewfinder: 1.1inch colour LCD

Flash Mode: Automatic

Shoot Mode: Single/Continuous/Self-timer

Exposure: Automatic

White balance: Automatic

Self-Timer: 10 seconds delay

Computer interface: USB1.1

Lens: fixed focus lens, F=2.8

Focus range: 25cm ~inf

Shutter speed: 1/15~ 1/4000s

Power supply: 2 x AAA battery (not included)

Dimensions; 90 x 33.5 x 57mm

System Requirement For PC: Windows 98/2000/ME/XP